Digital audio technology has greatly changed the landscape of music and entertainment. Rapid increases in computing power coupled with decreases in cost have made it possible individuals to generate finished products having a quality once available only in a major studio. Once consequence of modern technology is that legacy media storage standards, such as reel-to-reel tapes, are being rapidly replaced by digital storage media, such as the Digital Versatile Disk (DVD), and Digital Audio Tape (DAT). Additionally, with higher capacity hard drives standard on most personal computers, home users may now store digital files such as audio or video tracks on their home computers.
Furthermore, the Internet has generated much excitement, particularly among those who see the Internet as an opportunity to develop new avenues for artistic expression and communication. The Internet has become a virtual gallery, where artists may post their works on a Web page. Once posted, the works may be viewed by anyone having access to the Internet.
One application of the Internet that has received considerable attention is the ability to transmit recorded music over the Internet. Once music has been digitally encoded into a file, the file may be both downloaded by users for play, or broadcast (“streamed”) over the Internet. When files are streamed, they may be listened to by Internet users in a manner much like traditional radio stations.
Given the widespread use of digital media, digital audio files, or digital video files containing audio information, may need to be identified. The need for identification of digital files may arise in a variety of situations. For example, an artist may wish to verify royalty payments or generate their own Arbitron®-like ratings by identifying how often their works are being streamed or downloaded. Additionally, users may wish to identify a particular work. The prior art has made efforts to create methods for identifying digital audio works.
However, systems of the prior art suffer from certain disadvantages. For example, prior art systems typically create a reference signature by examining the copyrighted work as a whole, and then creating a signature based upon the audio characteristics of the entire work However, examining a work in total can result in a signature may not accurately represent the original work. Often, a work may have distinctive passages which may not be reflected in a signature based upon the total work. Furthermore, often works are electronically processed prior to being streamed or downloaded, in a manner that may affect details of the work's audio characteristics, which may result in prior art systems missing the identification of such works. Examples of such electronic processing include data compression and various sorts of audio signal processing such as equalization.
Hence, there exists a need to provide a system which overcomes the disadvantages of the prior art.